Crop MLT :: tilegroxy Docs

Description

This is the MLT equivalent of the cropmvt provider. A child known to produce MVT is rejected when the configuration is loaded.

Tiles entirely inside the bounds are returned unchanged. Tiles that cross the bounds are decoded, clipped, and encoded again using the simplest MLT encodings, so they can be somewhat larger than the original. Clipping also drops any pre-tessellated polygon data, which MapLibre rebuilds from the polygon outlines. Only version 1 MLT layers can be clipped, so layers in any other version are removed from tiles that cross the bounds. To guard against malicious tiles, a layer is also removed if decoding it would take the tile past roughly 50 MiB of memory, and any feature over roughly 10 MiB is removed from its layer.

Example

YAML
JSON

provider:
  name: cropmlt
  bounds:
    south: 51
    north: 63
    west: -7
    east: 0.1
  primary:
    name: pmtiles
    file: /data/basemap.pmtiles

{
  "provider": {
    "name": "cropmlt",
    "bounds": {
      "south": 51,
      "north": 63,
      "west": -7,
      "east": 0.1
    },
    "primary": {
      "name": "pmtiles",
      "file": "/data/basemap.pmtiles"
    }
  }
}

Configuration

Configuration options
Parameter	Description	Type	Required	Default
`primary`	The provider of the vector tile to crop	Provider	Yes	None
`bounds`	Any geometry that falls outside these geographic bounds (in WGS-84/EPSG:4326) will be removed.	Object with north, south, east, west	No	Whole world
`boundsFromAuth`	If true, use the bounds supplied via the auth context such as the geohash claim in JWT auth. If no bounds are specified via auth context then it falls back on the bounds parameter.	Boolean	No	No